/*
 * Copyright (C) 2011 Christopher Probst
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * * Neither the name of the 'FoxNet AIO' nor the names of its 
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.foxnet.aio.impl;

import java.io.IOException;
import java.nio.channels.AsynchronousChannel;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import com.foxnet.aio.EventQueue;
import com.foxnet.aio.EventQueueManager;

/**
 * @author Christopher Probst
 */
public final class EventQueueManagerImpl implements EventQueueManager {

    // Create workers
    private final QueueWorker[] workers = new QueueWorker[Runtime.getRuntime()
	    .availableProcessors() * 2];

    // We always use a cached thread pool
    private final ExecutorService pool = Executors.newCachedThreadPool();

    private int nxtWrk = 0;

    public EventQueueManagerImpl() {

	// Start all workers
	for (int i = 0; i < workers.length; i++) {
	    pool.execute(workers[i] = new QueueWorker());
	}
    }

    /*
     * (non-Javadoc)
     * @see java.io.Closeable#close()
     */
    @Override
    public void close() throws IOException {
    }

    /*
     * (non-Javadoc)
     * @see com.foxnet.aio.EventQueueManager#createEventQueue(java.nio.channels.
     * AsynchronousChannel)
     */
    @Override
    public synchronized <C extends AsynchronousChannel> EventQueue<C> createEventQueue(
	    C channel) throws IOException {

	EventQueue<C> q = new EventQueueImpl<C>(channel, workers[nxtWrk++]);
	if (nxtWrk == workers.length) {
	    nxtWrk = 0;
	}
	return q;
    }

}
